The decision to cancel the vote result, the first of its kind in Kenya’s history, sets up a new race for the presidency between Kenyatta and veteran opposition leader Raila Odinga. The verdict was backed by four out of the six judges.

East Africa’s biggest economy has a history of disputed elections. A row over the 2007 poll, which Odinga challenged after being declared loser, was followed by weeks of ethnic bloodshed in which more than 1,200 were killed.

Odinga has contested the last three elections and lost each time. Each time, he has claimed the votes were marred by rigging. In 2013, the Supreme Court dismissed his petition.

This time, his team focused on proving that the process for tallying and transmitting results was flawed, rather than proving how much of the vote was rigged.